Scott Alexander’s definition of signaling: a method of conveying information among not-necessarily-trustworthy parties by performing an action which is more likely or less costly if the information is true than if it is not true.

Batesian mimicry is parasitic in that one species (the most edible one) benefits to the detriment of the model species. It can only be maintained if the harm caused to the predator by eating the model outweighs the benefit of eating the mimic. –Sterns & Hoekstra. Evolution: An Introduction (5th ed.). p. 464.

Katrina: To clarify, it’s hard for me to tell where the truth lies on the cost/benefit analysis of making a child. It isn’t hard to predict a child’s impact on carbon emissions. That’s clearly a cost.